← #3 .
What do you mean by "saving option is not there" ?
The file created when you see the cross hair,
.. and select the `nam area´ you want for an image,
is saved when you release the mouse button.
Saved as e.g. screen12345.jpg to one of three locations :
/home/name/Desktop/, /home/name/, or /home/name/Documents/ .
... I.e. the save location can vary with "Desktop Environment".
( Gnome, KDE, Mate, etc.)